How to Write Numbers 11 to 20 in Japanese

I saw someone ask this question on WikiAns and decided to contribute and also create a blogpost about it as well.

Knowing how to write and say the numbers 11-20 in Japanese is easy once you see the pattern. Once you "get" this, I guarantee you'll find it easy to write numbers in Japanese from now on.

So what's the Pattern?

There's a general relationship between the way you write the numbers 11-20 in English and how you write it in Japanese characters. Look at numbers mathematically and treat each number as adding the 'tens-number' with the 'ones-number'. [Note the slight difference in the number 20.]

For example:
[number] = [what it means mathematically] = [romaji] = [kanji] = [hiragana]

[11] = [10+1] = [juu ichi] = [十一] = [じゅいち]
[12] = [10+2] = [juu ni] = [十二] = [じゅうに]
[13] = [10+3] = [juu san] = [十三] = [じゅうさん]
[14] = [10+4] = [juu yon] = [十四] = [じゅうよん]
[15] = [10+5] = [juu go] = [十五] = [じゅうご]
[16] = [10+6] = [juu roku] = [十六] = [じゅうろく]
[17] = [10+7] = [juu nana] or [juu shichi] = [十七] = [じゅなな] or [じゅうしち]
[18] = [10+8] = [juu hachi] = [十八] = [じゅうはち]
[19] = [10+9] = [juu kyuu] = [十九] = [じゅうきゅう]
*[20] = [2x10] = [ni juu] =  [二十] = [にじゅう]

Do you see the pattern yet?
Learning how to write numbers in Japanese and how to say numbers in Japanese is closely related. Take the time to really understand this. You'll be glad you did. :)

> Eager to go shopping in Japan? Surely you'll need more knowledge than this since Japanese products are sold in the 100s and 1000s. This course will show you how to be fluent in practical Japanese (the kind you're likely to hear in the streets of Tokyo) and more. --> Visit here to find out more now!